As specified in a Long Term Evolve (hereinafter referred to as LTE) protocol, a common pilot symbol may be used to obtain a channel estimation value needed for data demodulation. When the common pilot symbol is used to obtain the channel estimation value needed for data demodulation, an eNodeB first determines a precoding matrix used by user equipment (hereinafter referred to as UE), and notifies the UE of a precoding matrix index (hereinafter referred to as PMI) corresponding to the precoding matrix. The UE may obtain, according to a common pilot and PMI, the channel estimation value needed for data demodulation. In a Multiple User Multiple Input Multiple Output (hereinafter referred to as MU-MIMO) working mode, the eNodeB also needs to notify the UE of a power offset. The UE may obtain, according to the power offset, whether a matching UE exists currently, and then obtains, according to the common pilot, PMI, and power offset, the channel estimation value needed for MU-MIMO data demodulation.
When a dedicated pilot symbol is used to obtain the channel estimation value needed for data demodulation, a pilot symbol is combined with a data symbol together for transmission in a time division/frequency division multiplexing mode in a dedicated pilot channel. During data transmission, the eNodeB notifies the UE of the number of transmission layers used for data transmission. At a receiving end, after the UE receives a receiving signal, the UE obtains, according to the number of transmission layers and a pilot resource that is used for transmitting the pilot symbol and corresponds to each transmission layer, the channel estimation value needed for data demodulation, and performs corresponding data demodulation according to the channel estimation value to obtain service data. The eNodeB may notify the UE of a code word of the pilot resource corresponding to each transmission layer, or the eNodeB may preset the code word of the pilot resource corresponding to each transmission layer with the UE.
In a MU-MIMO transmission mode, channel estimation is performed according to the number of transmission layers only, which causes channel estimation performance to decrease or ever a data demodulation error.